On Super-Earths and Alpha Centauri — Centauri Dreams

On Super-Earths and Alpha Centauri

by PAUL GILSTER on NOVEMBER 13, 2012

The discovery of Centauri B b, a small planet with a mass similar to Earth, continues to percolate in the news even if the initial buzz of discovery has worn off. Science News gives the new world a look in a recent article, noting the fact that with an orbital period of 3.236 days, this is not a place even remotely likely for life. Surface temperatures in the range of 1200 degrees Celsius are formidable obstacles, but of course the good news is the potential for other planets around Centauri B and, indeed, around its larger companion.

Centauri A may well host interesting worlds, but it’s a tough study because it’s given to the kind of stellar activity that can more readily mask a planetary signature than the quieter Centauri B. Even so, we can imagine the possibility of two planetary systems in close proximity, a scenario that would surely propel any technological civilization around one to investigate the other. We don’t have the driver for spaceflight in our system that an Earth-like world around Centauri B might have, a second habitable planet breathtakingly close around another star.

If we’ve ruled out planets larger than Neptune around any of the three Alpha Centauri stars, that leaves the door open for the small worlds that could be the most interesting if one or more turned up in the habitable zone, and it’s worth noting that on this score, Proxima Centauri is still in the game. But right now the incredibly tricky detection of Centauri B b needs confirmation, which could be delivered by Debra Fischer (Yale University). You’ll recall that Fischer has been working at Cerro Tololo (CTIO) in Chile to develop the high-resolution spectrometer known as CHIRON, commissioned in March of 2011, as part of her team’s search for rocky Alpha Centauri planets.